Another caecal polyp

A 50 yr old patient complains of some low abdominal discomfort and undergoes a CT (image 1) following which a colonoscopy is organised to examine the caecum (video). 
WHAT IS THE MOST APPROPRIATE MANAGEMENT? 

■ Biopsies only

THERE'S NO NEED FOR BIOPSIES

■ Snare Polypectomy

There is no need to remove this

■ EMR

There is no need for a polypectomy

■ ESD

INCORRECT!

■ Surgery

CORRECT, THE CT TELLS YOU THIS!

explanation

The CT shows a large appendiceal mucocoele (see arrow below) and of course therefore, this is simply a prolapsed appendix.  More than 90% of our FoE group got this right.   

​Appendiceal mucocoeles are rare, incidence of 0.07 % - 0.3 % with a female predominance (M:F 1:4), and mean age at presentation of around 50 years. It most cases it is an incidental finding at for example ultrasound, laparoscopy or colonoscopy.

The most likely aetiology is proximal obstruction of appendiceal lumen due to chronic inflammation and subsequent cicatricial contraction. Continued production of mucous from the distal appendiceal cells lead to large collection of mucus within the lumen.

Noriko Suzuki told us the story of her as a junior endoscopist taking a biopsy from a mucocele, following which pus started coming out from the biopsy site!  Following which the patients abdominal pain improved.  She thought that she had treated the patients appendicitis but of course the abdominal pain recurred a few days later.

Of course, an open appendicectomy is the treatment of choice. It has been proposed that a laparoscopic resection may be linked with a greater risk of iatrogenic rupture of the cyst. Leakage of the gelatinous material into the peritoneal cavity may lead to peritoneal dissemination of thick mucinous blobs causing recurrent intestinal obstructions, a condition called “Pseudomyxoma peritonei”.

Pseudomyxoma peritonei carries a significant morbidity due to recurrent hospitalizations and a reported mortality of 50% in 5 years (Hinson 1998). There is a second reason to recommend surgery and this is the potential for malignant progression to “mucinous cystadeno-carcinoma”.